Summary and Conclusions
- Reliance on symptoms, VA reduction and fundus abnormalities may miss early Plaquenil toxicity. For unknown reasons, the foveal cones remain intact while a pericentral scotoma develops, often not noticed by the patient.
- Central visual fields (such as the 10-2), perhaps fields to a red stimulus, and color vision should be considered.
- Since Plaquenil toxicity can persist even after discontinuation of the medication, early diagnosis is crucial.
More advanced procedures, such as FA, widefield imaging with optomap®, SD OCT and mfERGs may prove to be superior in early detection.
- Based upon the cumulative dose of Plaquenil, the range of patients with an abnormal mfERG is 10%- 41%.3
- In addition, fundus autofluorescence is a promising non-invasive technique that has been reported to reveal a pericentral ring of autofluorescence early in the disease process. This will be explored in future cases.